This invention pertains to a vehicle for towing persons which moves on rollers or gliding bodies in accordance with the preamble to claim 1.
In past years movement on rollers or runners has become increasingly important For example, skateboards, mountainboards, longboards, skateboards, or inline skates are used to move on rollers. Movement on gliding bodies can be performed by means of ice skates, sleds, snowboards, skis. and other devices, special gliding bodies also being used to move on water. Persons who use the sport devices mentioned to move will be called skaters below.
The maximum speed of a skater who moves by means of his own muscle power depends on his musculature and fitness as well as the slope of the path travelled. Obviously, the means of locomotion is also important.
Experience also shows that many skaters would very much like to travel faster than their musculature, fitness, or the route travelled allow. In downhill competitions in which the skaters travel down closed inclines, maximum speeds of 80 km/h are attained for example. The world record for the speed of an inline skater towed by a race car is in excess of 300 km/h.
With today""s inline skates an average skater can travel about 35 km/h on a level road using his own physical strength.
Therefore, higher speeds can only be achieved using a towing vehicle. There is a need to present a vehicle to tow persons, in particular on rollers or gliding bodies, which achieves high speeds, which can be steered and braked safely despite a relatively high weight and, nevertheless, is easy to handle and to transport.
A vehicle for towing persons on rollers is known from U.S. Pat. No. 4,456,089-A, the towing vehicle having a motor drive which drives a drive wheel mounted in a chassis. The towing vehicle can be steered by the person by means of a longitudinal column. The problem with this device is that the complete weight of the vehicle, with motor, gears, tank, and chassis, as for example with the inclination illustrated in FIG. 1, has to be held by the person to be towed, the weight being increased by the drive torque during acceleration or reduced during bracing. Consequently, the vehicle weight and the torque of the motor produce uncontrollable forces which can no longer be controlled by the skater, especially at high speeds. Therefore, severe accidents can result.
In the case of the device known from U.S. Pat. No. 5,385,210, the dead weight of the towing vehicle is definitely better balanced but the acceleration and braking forces cannot be controlled with this device, either, so that problems similar to the prior art described above result.
Similar devices, but to push a moving person are known from U.S. Pat. No. 5,562,176. A means of locomotion in the form of a vehicle for pushing skiers with a crawler drive is known from WO 97/18866.
None of the devices described is suitable for high speeds such as desired in racing events in particular, because they are not safe enough and do not have the required ease of handling. In addition, none of the known devices is suitable for towing on snow surfaces.
Therefore, this invention is based on the technical problem of presenting a vehicle for towing persons which moves on rollers or gliding bodies which is driven by a motor and is suitable for high speed movement, especially on asphalt or snow, can be steered, accelerated and braked safely, and can be handled easily.
This problem is solved by the invention specified in claim 1. Advantageous further developments of the invention are specified in the sub-claims.
The inventive device pertains to a towing vehicle which has a drive wheel mounted in a chassis, the person being able to steer the towing vehicle by means of a steering column. In accordance with the invention, the chassis also has a support wheel located behind the drive wheel, the steering column being fixed to the chassis by a pitch point running parallel to the axis of rotation of the drive wheel, said pitch point being situated in front of the axis of the drive wheel. In addition to the drive wheel, the support wheel supports almost the entire weight of the chassis, the motor, the tank, etc. so that the person to be towed does not have to carry the dead weight of the towing vehicle. As the speed increases, the wheel load of the support wheel increases on account of the towing load and the pressure of the travelling wind on the housing of the towing vehicle. Furthermore, the support wheel absorbs the acceleration forces so that no additional torque impacts on the steering column just as the person starts to move. A suitable arrangement of the weight distribution on the towing vehicle also allows the braking forces to be equalized without any problem so that the towing vehicle cannot somersault during braking.
In order to be able to change the position of the steering column with regard to the chassis in a flexible manner, a pitch point running parallel to the axis of rotation of the drive wheel is located between the chassis and the steering column, said pitch point being situated in front of the axis of the drive wheel. Preferably the pitch point is combined with a spring element so that the steering column can be held in a basic position without weight forces having to be absorbed. Where desired, the steering column can be raised and, therefore, the load on the support wheel reduced, depending on the adjustment of the spring characteristic, and, if necessary, it can be raised quite high, for example if a tight corner is to be taken. The raising of the steering column can be facilitated if a substantial portion of the weight of the towing vehicle (e.g. in the form of a lead package) is placed in front of the drive axis.
In order to further reduce movements of the chassis with respect to the steering column, there can be an intermediate steering element which is fixed between the pitch point and a spring joint on the chassis. The spring joint is preferably located on the chassis between the drive wheel and the support wheel. The joints can also be equipped with shock absorbers. Preferably the springs on the pitch point or the spring joints are designed so that their resilience can be adjusted.
In further embodiments the support wheel can also be spring-mounted with respect to the chassis in order to reduce the effect of impacts on the chassis. The support wheel can also be motor-driven. For use in snow, the support wheel and drive wheel can be connected with one another by means of a revolving creeper band.
In order to be able to also employ the towing vehicle for other purposes, it can have a connecting device to which, for example, a wagon or the like can be attached.
The inventive design of the towing vehicle allows it, especially in its preferred embodiments, to achieve high speeds on different surfaces. A powerful motor can be used, which is required for high speeds and is suitable for that purpose. The torque of the motor is absorbed smoothly. The towing vehicle can be accelerated and braked without the skater having to move out of a relaxed driving position. He does not have to generate any force to hold the handlebar.
In the case of the preferred design with dual spring system, ground regularities are dampened and high speeds facilitated. At high speeds the person being towed shifts his own center of gravity downward. The structure of the towing vehicle also moves downward supported by the pressure of the travelling wind and of the towing load of the skater and is always at an optimal angle to the skater""s arms. During braking the skater supports himself with his body weight against the steering element. In accordance with the braking intensity, the chassis is pressed downward as a result of the placement of the pitch point, preventing the towing vehicle from somersaulting.